How to Create a Multiaxis Wireframe Operation

Introduction

This tutorial explains how to create a Multiaxis Wireframe operation.The wireframe operation requires a Drive Curve selection to define the toolpathand Orientation Lines selection along the curve to define the tool orientation.

Example File

If you are connected to the Internet, the part file for this example can be downloaded automatically by clicking the following link: Multiaxis WireframeExample 1.sldprt

Once you download and saved the zip file, extract the files on your system in an easy place to remember.You can then open the file to use with this tutorial.All files for the tutorials in this help system available for download can be found by clicking on the following link: http://www.bobcad.com/helpfiles.

In the example file provided,the stock and Machine Setup are already defined for the part.The partis simulated using the BC Table-Table machine.

In this example, you apply a trim cut to the bottom surface of the part.This example explains how to create all the geometry that is needed forthe feature directly from the part model.You also learn how the chaindirection of the drive curve and orientation lines define the toolpath.An important section here explains how to set the side tilt angle to createthe proper tool orientation for the feature.The last part shows how toforce the tool past the drive curve in order to cut with a different partof the flute.

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Part 1) Add the Feature

  1. In the PropertyManager, click the CAM Tree tab.

  2. Right-click MachineSetup and click Mill Multiaxis.

  3. In the MultiaxisWizard, click Wireframe.

  4. Click Next>>to go to the Posting dialogbox.

Part 2) Define the Posting Parameters

  1. The Work Offset # is automatically set tothe value defined in the Machine Setup dialog box.

    You can change the value here to update the Work Offset # for the feature.

  2. Click Next>>to go to the Multiaxis Postingdialog box.

Part 3) Define the Multiaxis Posting Parameters

  1. Notice, at the top of the dialog box, that the Use Machine Settings checkbox is selected.

This means that the Multiaxis Posting parametersfor the feature use the same parameters as the machine that is selectedin Current Settings.

You can clear the UseMachine Settings check box to define the Multiaxis Posting parametersof the feature separately from the current machine settings.

An example usage is explained later.

  1. Click Next>> togo to the Tool page.

Part 4) Define the Tool Parameters

  1. In the ToolData group, set the Diameterto 0.375 and the CornerRadius to 0.00.

  2. To assigna tool holder, clickAssignTool Holder.(If the HolderLabel already displays the holder name, you can skip this step.)

    In the Milling Tool Holder Library,in the CAT 40 Holder list,click 0.375 inch I.D. Arbor CAT 40,and click OK.

  3. Click Next>>to go to the Parameters dialogbox.

Part 5) Select Geometry

  1. On the Surface

Part 6) Set the Direction of the Orientation Lines

You must confirm that all of the OrientationLines share the same chain direction.For this example, all of theOrientation Lines must point towards the outside of the part.

  1. To view the chain direction, first clickFinish to close the wizard.

  2. In the feature in the CAM Tree, right-click Orientation Linesand click Modify.

    (You may need to expand the Geometry folder under theMultiaxisoperation.)

  3. The start point of each orientation lineis now visible in the graphics area.



  4. To change the chain direction, click neareach entity in the desired direction as shown next.

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  5. Continue this process until the directionof all orientation lines point to the outside of the part.

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  6. To accept the changes, in the PropertyManager, click OK.

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Tip: Asshown in this example, the chain direction of the Orientation Lines isset to start at the tool tip and point back towards the spindle.The chaindirection does not point towardsthe tool tip.

Ifan error message displays a warning about antiparallel lines, then allof the Orientation Lines are not pointing in the same direction.RepeatModify Start Point and correct the backwards chain direction.

Part 7) Set the Direction of the Drive Curve

  1. The chain direction of the drive curve mustalso be set.

The Drive Curve chain direction must be setto properly define the cutting direction and side based on the feature(open or closed) and the selected operation parameters.

To properly set the direction, first press CTRL+1to select the Front view of the part model.

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  1. To hide the part, in the Feature Manager design tree,click Part Model and clickHide.

  2. To view the chain direction, in the CAM Tree, right-click DriveCurves, and click Modify.

    You may need to zoom-in to view the start point.

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  3. Confirm that the chain direction is counter-clockwise as shownin the previous image.

Regardless of the current direction, click OK.

If the direction was clockwise, right-click Drive Curves,and click Reverse Direction.

Part 8) Define the Parameters

  1. Right-click FeatureMultiaxis and click Edit.

Click Parameters.

In the Pattern group, the MaximumSnap Distance defines what Orientation Lines are included in thetoolpath calculation.This distance is measured from the selected DriveCurve.

For this example, because the orientation linestouch the drive curve, the default value of 0.100is used.

  1. Because the chain direction is counter-clockwise (using theFront view), set the Machining Sideto Right.

  2. In the Sorting group,next to Direction for One Way Machining,select Follow Curve Chaining.

  3. To create the feature toolpath, at the bottom of the dialogbox, click Compute.

The toolpath is currently at the selected drivecurve edge, which is not the desired result.

To view the location of the toolpath compared tothe drive curve, in the CAM tree, click DriveCurves.

The drive curve preview displays in the graphicsarea.

Currently the tool orientation is not thesame as the selected Orientation Lines.The Tool Axis Control containsa tilting parameter, Tilt Away from Line, that determines the amount ofside tilting applied to the tool from the Orientation Lines in the directionof cut.

Important: Inorder to have the tool orientation follow the same orientation of theselected Orientation Lines, you must define the Tilt Away from Line parameteras 0.00 degrees.

Part 9) Define the Side-Tilt Angle

  1. Edit the feature, and click Parameters.

  2. Click the ToolAxis Control tab.

    Notice the tilting strategy, next to ToolAxis Will, is set to Be tilted relative to cutting direction.

  3. In the TiltAway from Line box, type 0.000.

  4. To calculate the toolpath, click Compute.

The toolpath is now offset to the bottom side ofthe part.This is the desired result.

(To show the part, in the Feature Manager design tree, clickPart Model and click Show.)

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  1. To view the simulation, menu, click Simulation.

During simulation, the tool orientation is now thesame as the Orientation Lines.

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  1. To close simulation, in the BobCAMmenu, click Exit Simulation.

Adjust the Machine Table Rotation

When you simulate the program, the machine table is sometimes rotated in a way that doesn't allow you to view the part without rotating the view of the machine. You can change the Angle Pair settings for the feature to modify the table rotation used in simulation and in the posted code.

 

  1. To edit the feature, in the CAM Tree, right click FeatureMultiaxis, and click Edit.

  2. Click the Multiaxis Posting icon in the tree.

  3. Clear the Use Machine Settings check box.

  4. In the Angle Pair group, next to Use, select Other Solution.

    When you simulate the program again, you can now view the part being cut from the opposite side of the machine.

    The table is rotated to use the other solution to the rotation angles of the primary and secondary rotary axes (angle pair). This changes the posted output of the program as well as the simulation.

 

Tip: You don't have to compute the toolpath to update this setting for simulation, but you must Post the program to update the code if has already been posted.

 

Part 10) Axial Shift

If you want to force the tool past the drive curve in order to cut usingmore of the flute, or a different part of the flute, you can use the AxialShift parameters.

  1. Edit the feature, click Parameters,and click the Utility tab.

  2. In the AxialShift group, notice the option Constantfor Each Contour.

    This shifts the tool by the specified amount for the entire toolpath.

  3. In the Tobox, type -0.250.

    (Negative values cause the tool to in-feed, and positive values retractthe tool.)

  4. To add the changes, click Compute.

The result is visible in the toolpath display.

The following images show the tool position beforeand after adding the Axial Shift.

Before After

This concludes the tutorial.

Related Topics

Multiaxis Wireframe